1. Field of the Invention
This invention relates to a dust collector, particularly to one with a function of secondary collection.
2. Description of the Prior Art
As shown in FIG. 1, a conventional dust collector is commonly used to collect dust or waste powder generated during operation in factories. The conventional dust collector is mainly composed of a bottom base 1, a supporting frame 2 installed above and at two sides of the bottom base 1, an air guiding box 3 fixed above the supporting frame 2, a motor 4 set above the right side of the air guiding box 3, a suction tube 5 set below the right side of the air guiding box 3 to correspond to the motor 4, a filtering bag 6 set above the left side of the air guiding box 3, and a dust bag 7 set below the left side of the air guiding box 3 to correspond to the filtering bag 6. Installed inside the air-guiding box 3 are blades (not shown in the FIG.) driven by the motor 4. In using, the blades are driven by the motor 4 to rotate to start sucking in the suction tube 5 to keep dust or powder sucked in from the end of the suction tube 5 to the other side of the air guiding box 3, and then let air pass through a filtering bag positioned above and keep dust and waste powder dropping down to the dust bag 7.
However, as the filtering bag 6 and the dust bag 7 are not separated by any isolating devices installed between them, dust or waste powder supposed to drop in the dust bag 7 may flow to and attach on the filtering bag 6 to clog air holes thereon. So, the filtration bag 6 must be often replaced to maintain smooth filtration, causing an increase of cost and an inconvenient use.